Saudi Arabia's Crown Prince Mohammed bin Salman is in Washington D.C. Tuesday, and will likely talk to President Donald Trump about something the Saudis have wanted for a long time: a nuclear energy program.

"This is the Saudis saying openly what we have known for a long time," said Ryan Turner, senior risk analyst at consultancy PGI Group. "Saudi Arabia's desire for a civilian nuclear program cannot be separated from the rivalry with Iran."

For around five years now, the Saudis have been in informal negotiations with the U.S. and other countries that could sell it nuclear reactors, with the stated aim of diversifying its energy base. And in February, the kingdom recruited American lobbying firm Pillsbury Winthrop Shaw Pittman as an advisor on the legal issues surrounding developing a commercial nuclear program.

The catch? Saudi Arabia is refusing to accept a deal that would forbid it from enriching uranium and reprocessing plutonium, the mechanisms necessary not for nuclear energy but for developing a weapon.

And the U.S. may not be able to afford to walk away: If it does, warns Turner, "they will pursue alternative suppliers such as China or Russia because they feel the program is needed in part to keep pace with Iran."

Dual-use technology: energy or weapons?

Opposition from U.S. lawmakers on both sides of the political aisle has historically impeded the kingdom's aims — Section 123 of the U.S. Atomic Energy Act of 1954 mandates that Congress review any sharing of nuclear technology with a foreign country.

Now, however, the Saudis have more cause for optimism: the Trump administration has signaled greater willingness to strike a deal than its predecessors.

The crown prince's talks with Trump this week will focus on national security issues and defense programs. In the past nine months alone, the U.S. has made $54 billion in foreign military sales to Saudi Arabia.

"Nuclear energy in Saudi Arabia is about more than just electrical power, it's about geopolitical power," Senator Ed Markey, a Democrat from Massachusetts, said in a statement following the crown prince's comments to CBS. "The United States must not compromise on nonproliferation standards in any 123 agreement it concludes with Saudi Arabia."

The U.S. has already achieved a civilian nuclear partnership in the Middle East under what nuclear energy experts call the "gold standard": its Section 123 agreement with the United Arab Emirates, which precludes the country from developing dual-use technology by barring uranium enrichment and fuel reprocessing. But the Saudis have made clear that this is not the agreement they want.

"There is real concern among U.S. lawmakers and non-proliferation experts about the spread of dual-use technology," said Turner at PGI Group. "Saudi Arabia's conduct in the war in Yemen hasn't helped its case."

Team USA versus Russia and China

The U.S. Nuclear Energy Institute (NEI) sees the potential agreement from an entirely different perspective.

According to Dan Lipman, vice president for suppliers, new reactors and international programs at the NEI, the U.S. would not only benefit from a nuclear partnership with Saudi Arabia — it would prevent the Saudis from making a less secure deal with the Russians or Chinese instead.

"From a geostrategic perspective, we want the Saudi economy to be diversified and healthy," Lipman told CNBC in a phone interview, adding that it could create thousands of American jobs. "We're very hopeful they pick team USA … If they partner with the Russians or the Chinese, we're on the outside looking in."

In response to concerns about the kingdom's nuclear intentions, the nuclear expert was unfazed.

"The Saudis are talking about deploying large light water reactors for electricity generation. No one develops the infrastructure and makes the investments necessary for commercial nuclear power plants as a route to a bomb," he said.

"And a 123 agreement with the U.S. ensures the world's highest standards for nuclear safety and non-proliferation ... If the Russians or the Chinese are there, those standards are not as tough."

A Middle Eastern arms race?

The agreement — currently under negotiation and whose parameters are to be outlined by the end of this month — coincides with the Trump administration's ongoing threats to withdraw from or renegotiate the Joint Comprehensive Plan of Action (JCPOA), a 2015 agreement signed with Iran and five other states to curtail its nuclear program while lifting economic sanctions.

The JCPOA contains sunset clauses on uranium enrichment bans. This is not lost on the Saudis, who are unlikely accept anything other than equal treatment with Iran by the U.S. — meaning only limited time restrictions on enrichment and reprocessing.

Meanwhile, speculation has grown about Saudi Arabia considering a deal with the Russians which would likely carry no conditions — and the Saudis are already increasing their cooperation with Russia in other areas.

Getty Images

A reactor building at the Russian-built Bushehr nuclear power plant in Bushehr, Iran.

But there are important differences between a Saudi deal and the existing Iran agreement, says Richard Nephew, program director at the Center on Global Energy Policy at Columbia University. Nephew served as the lead sanctions expert for the U.S. State Department negotiating with Iran from 2013 to 2014.

With Iran, "we were trying to contain an existing, uncontrolled problem then. With Saudi, it would be a whole new problem," Nephew told CNBC. "I do think there are real risks to a 123 agreement that includes enrichment for Saudi, at least as an option."

"Congress seeking a new gold standard just isn't realistic and it was not even before the JCPOA," he added. The delay in a Saudi deal, Nephew said, "was because Saudi wasn't interested in the gold standard."

Iran hit back at Bin Salman's bombshell comment last week, with its Foreign Ministry spokesman calling the crown prince a "delusional naive person" who did "not deserve a response."

The Iran deal, its supporters say, is crucial to preventing Iran's development of a bomb and to maintaining stability in a volatile region — dismantling it at a time like this could spell disaster.

"Saudi-Iran competition is already a major source of instability in the region, and that would only be amplified by the introduction of nuclear weapons," PGI's Turner said. "(Bin Salman's) comments are an accidental endorsement of keeping the Iran nuclear deal, which Trump appears increasingly likely to scrap in May."